The device makes brushing a game, enabling kids to earn points by holding and using the toothbrush correctly.

Williamson said the toothbrush would not be a big contributor to too much screen time for kids: "It´s just three brushings of two minutes each day."

The electronics show has long featured devices for children, and exhibitors typically plan their displays and products many months in advance.

But the show opened just amid fresh fears that too much technology may be harmful for children.

In the United States, the nonprofit group Common Sense Media found 95 percent of US households have a mobile device in the home. Screen time has been shifting, the group said, from television to mobile devices.

Earlier this week, two large shareholders urged Apple to study whether iPhones are proving addictive for children and if intensive use of the smartphones may be bad for their mental health.

The investors cited a recent study suggesting children are negatively distracted by digital technologies in the classroom.

Apple, which is not present at CES but whose system is used by many app developers, said in a statement it "has always looked out for kids, and we work hard to create powerful products that inspire, entertain, and educate children while also helping parents protect them online."

At CES, Ahren Hoffmann of the American Specialty Toy Retailing Association, said determining how much technology to use for kids is "all about balance."

"We want to make sure that our kids today are both getting outside and play, and that they are playing with traditional toys, that they´re playing board games, but they´re also using iPads and tech toys, and learning about coding and other things that are happening in the world around us today," she told AFP at the show.

Las Vegas: The children´s section at the giant Consumer Electronics Show this week touted "innovations that enable 21st century kids to learn and play smarter than ever. "

The timing may have been unfortunate following revived concerns of the dangers of too much technology for young children.

But as the debate swirled, exhibitors at the Las Vegas extravaganza sought to showcase devices aimed at health, education and entertainment for youngsters, including educational robots.

Pai Technology introduced its interactive storybooks for children, which use virtual reality and according to its website "encourages a love of reading" and offers "thoughtful stories."

Amy Braun, marketing director for the group, acknowledged concerns about kids and technology but said these devices still have value.

"Technology is here to stay, and it´s important to expose our children to technology but in beneficial ways," she said.

"We really focus on making sure that the time that we put it in front of our children is all about learning and development. And it´s not either or."

Braun said parents must decide on appropriate limits for screen exposure and other technology usage.

Chinese startup Dragon Touch unveiled its colorful tablet computer aimed at kids between three and six years old, with educational apps and parental controls.

Dragon Touch´s Lei Guo said the tablets may be valuable but also suggested parents supervise their use.

"I really don´t want my kids to spend too much time on the internet," he said.

"So that´s why we also have the parent control mode, so that the parents can set a time, for example maybe 30 minutes per day."

- Augmented reality toothbrush -

An augmented reality toothbrush meanwhile introduced by French startup Kolibree allows children to look at a smartphone or tablet screen to motivate and educate them about oral hygiene.

The device makes brushing a game, enabling kids to earn points by holding and using the toothbrush correctly.

Williamson said the toothbrush would not be a big contributor to too much screen time for kids: "It´s just three brushings of two minutes each day."

The electronics show has long featured devices for children, and exhibitors typically plan their displays and products many months in advance.

But the show opened just amid fresh fears that too much technology may be harmful for children.

In the United States, the nonprofit group Common Sense Media found 95 percent of US households have a mobile device in the home. Screen time has been shifting, the group said, from television to mobile devices.

Earlier this week, two large shareholders urged Apple to study whether iPhones are proving addictive for children and if intensive use of the smartphones may be bad for their mental health.

The investors cited a recent study suggesting children are negatively distracted by digital technologies in the classroom.

Apple, which is not present at CES but whose system is used by many app developers, said in a statement it "has always looked out for kids, and we work hard to create powerful products that inspire, entertain, and educate children while also helping parents protect them online."

At CES, Ahren Hoffmann of the American Specialty Toy Retailing Association, said determining how much technology to use for kids is "all about balance."

"We want to make sure that our kids today are both getting outside and play, and that they are playing with traditional toys, that they´re playing board games, but they´re also using iPads and tech toys, and learning about coding and other things that are happening in the world around us today," she told AFP at the show.